[aprssig] IRLP Node Object

[Heikki Hannikainen]

On Sun, 25 Mar 2012, Paul Yeager wrote:

> ;IRLP-4040*111111zDDMM.hhNIDDDMM.hhW0FFF.FFFMHz Tnnn CALLSIGN
> 
> ... and what I entered is:
> 
> ;IRLP-4397*111111z3522. NI08313. W0444.875MHz T131 K4RCC
> 
> My problem is that aprs.fi appears not to like the format. Viewing the raw
> packets reveals:
> 
> 2012-03-25 22:05:09 UTC: EGLNST>APN383,qAR,N4NE-1:;IRLP-4397*111111z3522. 
> NI08313. W0444.875MHz T131 K4RCC [Delayed or out-of-order packet (timestamp)]

aprs.fi uses the timestamp for duplicate/delayed and out-of-order packet 
filtering. If the timestamp suddenly jumps back, the packet is probably 
older than the previous packet from that station, and can be thrown away. 
(It's actually just a little bit more complicated than that, but that's 
the principle.)

http://aprs.fi/info/a/IRLP-4397 - The same station is already transmitted 
by K4RCC-13, which uses real UTC timestamps instead of a constant 111111z, 
so aprs.fi takes the 111111z packet as a delayed one.

It's probably not a problem for you if aprs.fi doesn't accept your packets 
- your target are the local RF-based stations, which probably do not see 
K4RCC-13's packets.

   - Hessu